Seagate Ultra160 Product Manual page 321

SCSI Interface Product Manual, Rev. B
SPC-2, T10/1236D, for the definition of diagnostic pages. A PF bit of zero indicates that all SEND DIAG-
NOSTIC parameters are vendor-specific.
[3] A SELF TEST bit of one directs the device server to complete the target's default self-test. If the self-test
successfully passes, the command shall be terminated with Good status; otherwise, the command shall
be terminated with CHECK CONDITION status and the sense key shall be set to Hardware Error.
A SELF TEST bit of zero requests that the device server perform the diagnostic operation specified by the
Self-test Code field or in the parameter list. The diagnostic operation might or might not require the device
server to return parameter data that contains diagnostic results. If the return of parameter data is not
required, the return of GOOD status indicates successful completion of the diagnostic operation. If the
return of parameter data is required, the device server shall either:
[a] perform the requested diagnostic operation, prepare the parameter data to be returned and indicate
completion by returning Good status. The application client issues a RECEIVE DIAGNOSTIC
RESULTS command to recover the parameter data; or
[b] accept the parameter list, and if no errors are detected in the parameter list, return GOOD status. The
requested diagnostic operation and the preparation of the parameter data to be returned are per-
formed upon receipt of a RECEIVE DIAGNOSTIC RESULTS command.
[4] A DEVOFFL bit of one grants permission to the device server to perform diagnostic operations that may
affect all the logical units on a SCSI target port, e.g., alteration of reservations, log parameters, or sense
data. The implementation of the DEVOFFL bit is optional. A DEVOFFL bit of zero prohibits diagnostic
operations that may be detected by subsequent tasks. When the SELF TEST bit is zero, the DEVOFFL bit
shall be ignored.
[5] A UNITOFFL bit of one grants permission to the device server to perform diagnostic operations that may
affect the user accessible medium on the logical unit, e.g., write operations to the user accessible
medium, or repositioning of the medium on sequential access devices. The implementation of the UNIT-
OFFL bit is optional. A UNITOFFL bit of zero prohibits any diagnostic operations that may be detected by
subsequent tasks. When the SELF TEST bit is zero, the UNITOFFL bit shall be ignored.
[6] The PARAMETER LIST LENGTH field specifies the length in bytes of the parameter list that shall be
transferred from the application client to the device server. A PARAMETER LIST LENGTH of zero indi-
cates that no data shall be transferred. This condition shall not be considered an error. If the specified
PARAMETER LIST LENGTH results in the truncation of one or more pages (PF bit set to one) the device
server shall return CHECK CONDITION status with a sense key of ILLEGAL REQUEST and an additional
sense code of Invalid Field in CDB.
Note. To ensure that the diagnostic command information is not destroyed by a command sent from
another initiator, either the SEND DIAGNOSTIC command should be linked to the RECEIVE
DIAGNOSTIC RESULTS command or the logical unit should be reserved.
[7] See Table 61, "CONTROL field," in Section 7.2.1.
[8] The FUNCTION CODE field values are given in Table 233.
303